Sprays 



(a) Sulphur-dusting. — Flowers of sulphur are 

 dusted over the affected parts, or those it is desired 

 to protect, by means of powder bellows specially 

 constructed for the purpose, or of a flour-dredger. 



(6) Sulphur-fumigation. — Sidphur is placed in a 

 specially constructed vessel and heated so as to be 

 vaporised, hut not burned ; the vapour is condensed 

 on the foliage, etc., and every part becomes covered 

 with a thin film of sulphur. A crude method of 

 effecting this has been in vogue, the sulphur being 

 heated on a hot iron plate, but there is great danger 

 of it bursting into flame, and the gas formed by burn- 

 ing sulphur is fatal to living plants. 



Another method of applying sulphur is that of 

 making a paste of it in milk and painting the hot- 

 water pipes. The heat of the pipes probably causes 

 the sulphur to be very slowly oxidised and the 

 poisonous gas to be produced in sufficient quantities 

 to check fungi effectively. 



(c) Liver of Sulphur, or potassium sulphide. — 

 Liver of sulphur is dissolved in water at the rate of 

 1 oz. to 3 gallons (or 1 oz. to 4 gallons, when tender 

 plants have to be sprayed). The soHd material 

 should be kept from the air or it speedily deteriorates, 

 and care should be taken to obtain only the soluble 

 forms. It is a useful fungicide, but stains white-lead 

 paint black. 



(d) Copper Compounds. — Liquids containing 

 copper are used, for the most part, for spraying 



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